Discussion
According to previous studies, unrepaired VSD is the most common
congenital abnormality associated with the highest risk of infective
endocarditis(1), followed by ventricular outflow tract obstruction(2).
Both these conditions were present in this patient. Berglund et al.
demonstrated that a small and unrepaired VSD could increase the
incidence of IE more than 20 times compared with the general population
(3).
Based on European Society of Cardiology guidelines, diagnosing
right-sided endocarditis is more challenging than the left side due to
the lower sensitivity of duke criteria (4), as our patient was diagnosed
with right-sided endocarditis with a remarkable diagnostic delay.
It has been shown that renal infarcts and non-immune complex-mediated
glomerulonephritis are the most common renal lesions in right-sided IE
by renal biopsy or necropsy examination. Septic embolism was the cause
of renal infarcts in more than half of the patients (5).
A study in France showed the existence of septic pulmonary emboli (SPE)
in up to 70% of right-sided IE(6). Diagnosing SPE can be challenging
due to nonspecific presentation and can remain unrecognized.
Subacute bacterial endocarditis (SBE) and ANCA-associated systemic small
vessel vasculitis have overlapping clinical manifestations. Awareness of
false positive ANCA tests in SBE and possible endocardial involvement in
idiopathic ANCA-associated vasculitis is important due to different
management(7).
Leukocytoclastic vasculitis can be a rare presentation of IE. A
retrospective study of 138 biopsy-proven cutaneous leukocytoclastic
vasculitis patients showed bacterial infection as the underlying cause
in 4 (2.9%), three diagnosed with IE(8).
In conclusion, IE has a wide variety of presentations, imitating
connective tissue disorders and vasculitis, so even subtle symptoms
should be considered seriously, especially in patients at high risk for
endocarditis.